Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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BIODEGRADABLE INSECT BAIT STATION
BACKGROUND OF THE INVENTION
[0001] The present invention relates in general to an apparatus for
dispensing pesticides, and more particularly to a biodegradable outdoor insect
bait station adapted to be anchored securely in the ground.
[0002] One of the most popular and effective methods of combating
crawling insects such as ants is to use poisonous bait which is commonly
positioned around or near the insect nest or near where insects gather food.
According to their usual food gathering habits, crawling insects will feed on
the
poisonous bait and take some of the bait with them back to their nests or
homes
where the bait is shared with other insects, preferably the queen, and as a
result
kill a large number of insects.
[0003] Various devices typically referred to as insect bait stations have
been utilized to present bait to crawling insects, and are well known. Typical
examples of outdoor insect bait stations are disclosed in U.S. Patent Nos.
2,837,861; 4,277,907; 4,485,582; 5,325,626; 5,746,021; 5,918,410; 6,164,010;
6,219,960; 6,298,597; 6,401,384; 6,467,216; 6,474,016 and 6,497,070. Each of
the bait stations disclosed in the above patents generally include a sealable
container and a spike or stake attached thereto for insertion into the ground.
A
plurality of access holes are provided either in the stake or in the container
which allow the crawling insects to enter the interior of the container to
feed on
the poisonous bait.
[0004] There are also various devices designed to be embedded in the
ground for delivery of pesticides to target insects or for the delivery of
other
materials to the ground that are provided with components that may be
biodegradable or otherwise sacrificial. Typical examples of such structures
are
disclosed in U.S. Patent Noa 3,302,325; 3,962,822; 4,333,265; 4,336,669;
6,159,489; 6,202,342; and 6,419,943. Biodegradable structures advantageously
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eliminate the need to seek out the remnants of insect bait stations and
dispose
of them at a later date after the poisonous bait is depleted. There remains a
need, however, for an improved biodegradable outdoor insect bait station.
SUMMARY OF THE INVENTION
[0005] The present invention provides a biodegradable outdoor insect bait
station for offering a toxic bait to a target insect. The bait station
comprises a
bait matrix together with a housing for holding the bait matrix. When the bait
station is placed outdoors, the bait matrix biodegrades providing an appealing
food source for a target insect.
[0006] The bait matrix comprises a core of bait material which includes a
pest controlling amount of an active ingredient toxic to the target insect,
and a
biodegradable coating covering at least a portion of the bait core. When
placed
outdoors, moisture permeates the coating and liquefies the core making the
entire matrix a food source for the target insect. The housing includes at
least
one opening to permit the target insect ingress and egress from the interior
of
the bait station where it can feed on the bait. The housing advantageoursly
permits ease of handling the bait station, protection for the handler from the
bait
material, and ready access by ants to the bait.
[0007] In one particularly preferred embodiment, the bait matrix is in the
form of a spike having an inner core of solid bait material coveredby an outer
rigid sheath of biodegradable material, such as paper, with a head portion
disposed within the housing and a longitudinally extending stake projecting
through an aperture in the housing. In this embodiment, the bait station can
be
inserted into the ground until the housing is substantially flush with the
ground
so that it is inconspicuous and the bait material contained in the matrix and
within the housing is inacessible to household pets. The outer rigid sheath of
the matrix is biodegradable and the housing for holding the matrix may also be
composed of a biodegradable material which eliminates the need to seek out
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remnants of the station and dispose of them at a later date after the toxic
bait is
depleted.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The drawings illustrate the best mode presently contemplated of
carrying out the invention.
[0009] In the drawings:
[0010] Figure 1 is a perspective view of a biodegradable insect bait
station constructed in accordance with the principles of the present
invention;
[0011] Figure 2 is an exploded perspective view of the components of
the insect bait station; and
[0012] Figure 3 is a longitudinal cross-sectional view of the insect bait
station.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Referring now to the drawings, Figs. 1-3 illustrate a biodegradable
insect bait station generally designated by the numeral 1 and constructed in
accordance with the principles of the present invention. The bait station 1 is
comprised of a bait matrix generally designated by the numeral 2 together with
a hollow housing generally designated by the numeral 3 for holding the bait
matrix 2., When the bait station 1 is placed outdoors, the bait matrix 2
biodegrades providing an appealing food source for a target insect. It should
be
noted that although bait station 1 is designed primarily for use outdoors,
indoor
use is also possible by modifying the configuration of the bait matrix 2. In
addition, bait station 1 is intended primarily for offering a toxic bait to a
target
insect which is preferably a crawling insect such as an ant, a cockroach, a
spider, a beetle, a centipede and the like.
[0014] As used herein, the term "biodegradable" refers to a material that
has the ability to break down relatively quickly by biological means (e.g. by
microorganisms) into the raw materials of nature and eventually disappear into
the environment. Generally, any plant based, animal based, or natural mineral
based product has the capability to biodegrade, but products made from
manmade petrochemical compounds generally are not considered to be
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biodegradable due to the length of time for such materials to actually break
down in nature as a result of the action of microorganisms. Recently, however,
biodegradable plastic has been introduced which is intended to break up when
exposed to microorganisms in nature. In order to accomplish this, natural
ingredients such as corn starch or vegetable oil is added to render the
plastic
biodegradable. Examples of such biodegradable plastics include
available from
and available
from . Biodegradable materials generally
comprise one or more of paper, cotton, and
[0015] The housing 3 for holding bait matrix 2 is itself comprised of two
components, namely, a generally annular shaped bait holder 4 and a cap 5. As
noted above, both the bait holder 4 and cap 5 may be composed of a
biodegradable material, and in the preferred embodiment comprises
biodegradable plastic. As illustrated best in Figs. 2 and 3, bait holder 4 has
a
frustum-shaped outer wall 6 that extends upwardly to an upper rim 7 defming
an open top and extends downwardly to a lower rim 8 defining an open bottom
or aperture. Both the upper rim 7 and lower rim 8 are annular in shape with
the
diameter of upper rim 7 being greater than the diameter of lower rim 8.
Frustum-shaped outer wall 6 extends between rims 7 and 8 and provides a
tapered surface disposed at an angle of about 45 from a vertical plane that
extends longitudinally and parallel with respect rims 7 and 8. Upper rim 7
includes an annular recess 9 formed therein which cooperates with a like
recess
10 formed in cap 5 to provide a snap fit arrangement between cap 5 and bait
holder 4.
[0016] Cap 5 encloses the open top of bait holder 4 and comprises a
relatively flat ceiling 11 that spans the open top of holder 4 and extends to
an
outer periphery having a diameter substantially matching the diameter of upper
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rim 7. Cap 5 also includes an annular rim 12 extending downwardly from the
outer periphery of cap ceiling 11. Rim 12 includes, as described above, an
annular recess 10 at its lower edge which cooperates with recess 9 to provide
a
snap-fit arrangement for cap 5 on bait holder 4. Cap 5 also includes at least
one opening 13 formed in ceiling 11 to provide access to toxic bait by a
target
insect, i.e. to permit a target insect ingress to the hollow interior of
housing 3
and egress therefrom. As shown best in Figs. 1 and 2, there are eight equi
angularly spaced apart oblong shaped openings 13 formed in ceiling 11. As
apparent to one skilled in the art, the number of openings 13 as well as the
shape of each opening 13 may be varied as desired so long as a target insect
has
access to the interior of hollow housing 3 via those openings 13.
[0017] As shown best in Fig. 3, bait matrix 2 is comprised of a core 14
containing a bait with a pest controlling amount of an active ingredient toxic
to
a target insect, and a biodegradable coating 15 covering at least a pcrtion of
the
bait core 14. The insect bait is preferably in solid form, but may also be a
liquid, jell or semi-solid composition. As used herein, the term "bait" refers
to
any of a number of toxic formulations poisonous to a target insect, such as an
ant, which are well known in the art. Preferably, the bait is of the type
having a
delayed kill action so that crawling insects will feed on the poisonous bait
and
take some of the bait with them back to their nests or homes where the bait is
shared with other insects and as a result kill a large number of insects.
Examples, of a suitable insecticidal active ingredient toxic to insects
include
abamectin, hydramethylnon, boric acid, sodium borate, fipronil and/or
perfluorosulfonyl compounds, as well as others known to those skilled in this
art, commonly employed to kill crawling insects. These insecticidal actives
may be formulated like most hard candies using sugars, corn syrup and water.
The term "pest controlling amount of active ingredient" refers to providing an
effective amount of the insecticidal active sufficient to kill the target
insect.
Such amounts are well known in the art and may be varied depending upon the
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target insect as well as the rate of kill desired. However, typically
insecticidal
actives will be incorporated into a formulation in an amount of from about
0.01% by weight to about 10% by weight which would be adequate to provide
a pest controlling amount of the active ingredient. An example of a suitable
bait-toxicant formulation comprises: hydramethylnon (at 0.51% by weight) as
the insecticidal active, oleic acid (at 0.35% by weight) as a solvent for the
active, peanut oil (at 0.64% by weight) as a solvent for the active, sorbitan
monooleate (at 0.30% by weight) as an emulsifier, cane sugar (at 52% by
weight) as a food source, corn syrup (at 32% by weight) as a food source, and
water (at 14.20% by weight) as a solvent. Another example of a suitable bait
toxicant comprises: boric acid (at 2% by weight) as the insecticidal active
ingredient, sugar and corn sweetener (at 15% by weight) as a food source, a
preservative such as that commonly sold under the trademark "Legend MM" (at
0.2% by weight), carageenan (at 1.2% by weight) as an emulsifier, and water
(81.6% by weight) as a solvent. Once dried, the above liquid formulations
become solid and hard candy-like. Once exposed to moisture, it will absorb the
moisture, liquefy and provide a food source for the target insect. It should
also
be noted that moisture absorption by bait core 14 can be regulated by the
choice of sugars and syrups as is well known in the art. Also, feeding
acceptance by the target insect can be enhanced by the inclusion of additional
ant feeding stimulants such as
or , which is also well
known in the art.
[0018] Coating 15 is made of a biodegradable material and covers at least
a portion of bait core 14. Preferably, the biodegradable coating 15 is formed
of
a rigid biodegradable material such as paper. However, coating 15 could also
comprise a thin film of biodegradable plastic material if desired as well as
any
other biodegradable material which will initially protect bait core 14 but
will
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biodegrade to permit moisture to permeate therethrough and liquefy the bait
core 14.
[0019] In the preferred embodiment, bait matrix 2 is in the form of a
longitudinally extending spike having a head portion 16 disposed within bait
holder 4, a stake portion 17 projecting through the open bottom or aperture of
bait holder 4 to extend outside of bait holder 4 and terminate at a cone-
shaped
tip 18. As shown best in Fig. 3, the bait matrix 2 comprises a solid core 14
containing a bait with a pest controlling amount of an active ingredient toxic
to
the target insect, and a biodegradable rigid sheath 15 covering at the least
the
stake portion 17 and tip 18 of the spike. As illustrated, stake portion 17 is
frustum-shaped and has a taper of 45 to match the taper of the outer wall 6
of
bait holder 4 so that the head portion 16 will nest within bait holder 4. The
stake portion 17 of the spike will thus extend from the open bottom bait
holder
4 for easy insertion into the ground.
[0020] In use, the stake portion 17 and cone-shaped tip 18 are pushed into
the ground until housing 3 is substantially flush with the surface of the
ground.
After being pushed into the ground, moisture will permeate the coating or
sheath 15 and liquefy the bait core 14 thus making the entire bait matrix 2 an
appealing food source for a target insect. Since the entire bait station 1 may
be
biodegradable, bait station 1 eliminates the need to seek out the remnants
thereof and dispose them at a later date after the bait matrix is depleted.
[0021] While this invention has been described with reference to what is
currently considered to be the preferred embodiment, it is to be understood
that
the invention is not limited to the disclosed embodiment. On the contrary, the
invention is intended to cover various modifications and equivalent
arrangements included within the spirit and scope of the appended claims. For
example, the bait matrix 2 need not necessarily be in the form of a spike, but
may take other configurations as desired, especially if adapted for indoor
use.
Thus, the scope of the following claims is to be accorded the broadest
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interpretation so as to encompass all such modifications and equivalent
structures and functions.
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